Last night I got a shot of my wifes Ambiente Mk1 TDi on a country road that I know well. For only 20bhp less than my Elegance, the difference in flexibility was marked.

Whereas in my car you squeeze the throttle and effortlessly fly out of corners, with the Ambiente you had to work a lot harder and inevitably found your foot up tight against the carpet (it is a company car, so why not?) to come remotely close. I was still "pushing" the car on in places where in the Elegance I'd have started to back off a bit as I'd already be going fast enough!

I'm sure the difference comes from the torque rather than the bhp as 20 isn't a big difference. Thing is, I know stuff all about how engines work (Like most I know the theory, but this isn't the same as knowing how they work). So as result I'm interested to know what things are different between the two to get such a marked increase in performance?

Something to get you thinking before your works Christmas Meal!

Niall

There is a difference in the turbo design. Not sure about the technicalities but I think it's something to do with the 90bhp not having variable vanes.

Yep, the main difference is a VNT turbo. There are other differences though.

Injectors flow more with the 110, but not much more. If you're going to change nozzles there are better ones out there than the 110 injectors, which will flow lots....

VNT is the other thing, which means on the 90 there's not much you can do with the turbos, but the VNT17 off the PD130/PD150 engines will bolt right on to the 110 engine.